The use of plastic material for making optical lenses has increased rapidly for the past ten years. This is due to the availability of better plastic materials and the physical advantages of the plastic resins for specific applications such as contact lenses. The technology for the production of high quality bifocal contact lenses has not kept pace with the material supply industry. It is important to advance both areas if the full potential is to be realized.
The current bifocal lens molds are fabricated from metal or glass, each mold is individually ground and polished to the required specifications. To achieve accurate reproduction of the bifocal molds is most difficult and expensive. This new process makes possible exact reproductions by replication and has many other distinct advantages which will become apparent from the following disclosure.
The object of the invention is to provide a process for making inexpensive bifocal contact lenses which may be made to identical specifications.